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i must tell you that I am truly honored to give a lecture named for someone who contributed so much of his talent to benefit the industry in which I am involved. Dr. Robert Mehl worked at the Naval Research Laboratory (NRL.) in Washington, DC. He was a pioneer in the field of gamma radiography. Much of the work in which he was involved directly impacted Naval shipbuilding. I don't believe I can improve upon the words stated by the first recipient of this award, Charles Briggs, who incidentally also worked at NRL as a protege of Dr: MehL .He stated, "It is pleasant indeed to be able to honor, by this lectore, a living American scientist who has done so much for radiography. Gamma ray radiography, as compared to X-ray radiography, has been distinctly an American develop}nent, and it is with considerable pride that we recognize Robert Mehl as the one who Formulated and directed its development.
One of the most important aspects of this biennial lecture series is not so much what the guest lecturer has to say (albeit that is important, too). lather, it is the op- portunity to give due recognition and honor to the individual for whom the lec- tuxe was named Dx: Mehl was one of those pioneers who laid the very foundations of our technology and we should not forgethis contributions.
This presentation today is not about radiography It's about accuracy control. It's more akin to continuous quality improvement using the visual inspection method. I'm very pleased to see that our conference theme is "NDT一Keystone of Quality." NDT and quality (continuous improvement) axe inextricably linked. NDT' is becoming more proactive in the monitoring and continuous improvement of manufacturing processes. My discus-sion is along these lines.
Befoie i get involved in the detailed discussion, let me first give you a brief intro duction to the company
which this presentation is about, and which employs me.
Newport
News
Shipbuilding was founded in 1886 by Colic P .Huntington, a railroad magnate of his time. His vision was to build a repair yard to service the ships from around the globe which were engaged in the coal trade in Hampton Roads Harbor.
We launched our first ship in 1890 and since that time we have built, converted, or reconditioned nearly 800 ships of all types.The company is located on 550 acres, stretching more than two miles along the historic James River near the port of Hampton Roads, Virginia. We have eight drydocks, including the largest dock in the western hemisphere, and four piers.
We are the largest private employer inthe state and currently have 18,000 employees. Our sales in 199b were almost $1.9 bil-ion. We currently have construction contracts for two NIMITZ class aircraft carriers(the horry S: Truman and the Ronald Reugan) and eight commercial product tankers. We just delivered our first double bottom product tanker in September一our first commercial ship in nearly two decades. We also have a great deal of ship repair activity, both Navy and commezrial. We are currently engaged in the instal-lation of a ﹩70 millzon investment to modernize and automate our steel production facilities using robdtics and advanced computer-aided manufacturing and design technology. Also of particular note.is ourrecent spinoff by Tenneco to become“completely separate and independent company trading on the New York stock exchange under the call letters of "NNS." If you care to know more about our comPany, you can visit us on the World Wide Web at www.nns.com.
When Colis P Huntington founded NNS more thah 11 years ago, he had a vi sion which we have carved in a stone located in front of our facility. It reads:
We shall build good ships here.
At a profit if we can.
At a loss if we must.
But aIways good ships.
I can tell you the philosophy behind this statement stands today. It's also true that in today's business environment, Newport News Shipbuilding, like any other business, cannot afford to build products at a loss. Otherwise we won't be in business very long.And much of
what we're doing to avord Losses and be a world class ship- builder is the subject of this lecture: Acccura-cy Control.
Creating Accuracy ControlI
Dimensional accuracy control in structural shipbuilding is simply the planned activities
which ensure that selected dimen sional targets for each fabrication process
are met at minimum cost. Lef's put it in perspective.We are talking about building two separate multihundred ton structural assemblies, each as large as a house, in different locations, and then ensuring that when the two units are mated, the shell, decks, and internal structrue are aligned to within ±4 mm and ready to weld with a weld joint root opening of ±l mm，If this
sounds like pretty close tolerance, I can as-
sure you it is. But I'm here to tell you that some of our foreign competitors are meeting tolerances such as these 99 percent of the time.
Historically, shipbuildi ng was accompushed by laying the shell plates in place,
one at a time, and then adding the transverse and longitudinaI members one at a
time in the construction dock or way, leav-
ing holes in the structure through which
macnmery and otner outfitting materal
could be subsequently loaded.
As time moved on and as shipbuilding
became more sophisticated and facilities were able to support larger assemblies, more unitized construction began taking place in the shops and platens，and larger assemblies were brought to the building ways with much of the outfitting already accomplished.This modular method of
shipbuilding is certainly more productive, but it brings with it a higher degree of complexity and a need for greater dimensional control in order to reduce the amount of re-work to join two mating assemblies.
Accuracy Control一The Keystone of duality in Shipbuilding |
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发表于 2008-5-26 12:50
提升卡
变色卡
因为很忙，不能一字一句帮你，用了软件，不知道你自己组织下能否引用呢？
（脑子涨了，不知所云了）
要开会去了，暂时让其他大X帮你吧
楼主
大哥我也是金山快译，但是大哥，翻完发给你的时候我自己再组织下的，否则怎么好意思上传，肯定被版主嘲笑
